STORING STRING DATA FROM HC05 TO ARDUINO EEPROM

help me I made led scrolling display ,and i use hc05 bluetooth to send string data to arduino and it work but problem
is that when power is off all data is erase we send data again then they work
i want to store the data in eeprom and when we send command next time i want erase old data and new data is scrolling on display
sorry for poor english

i want to store the data in eeprom and when send next command i want old data is deleted and new data is scrolling on display

Go for it. There is nothing even remotely challenging in writing text to EEPROM, or reading it back, as long as you store less than 256 characters and store the count in the first address, and the text in addresses 2 through n (or store the length in the first 2 addresses, and the 255+ characters in 3 through n).

You will find examples in this link for data read/write operations with internal EEPROM of ATmega328P MCU of the UNO.

you might want to put a big cap across the arduino power pins and read it's voltage via an analog pin, we both know when power is gone, cap's voltage drops and that's when the check_routine kicks in when it drops further.. you quickly store the string into eeprom and your done